How about a rational national firearm control policy?
How is a "national firearm control policy" going to prevent something like this? You think the bad guy is going to put his guns away because of a policy? It's already against the law to bring weapons into schools. They can't follow law - you expect them to follow a "national gun control policy?" How idiotic.
A policy like that will only work if we can somehow convince the bad guys to start following the law.